This invention relates to a process and apparatus for special forming of a member in a cross-rolling forming process.
In the prior art cross-rolling forming process for forming a cylindrical member having a reduced diameter cylindrical portion at its intermediate portion connected to the opposite ends of the member by conical surfaces, respectively, the reduction ratio of the diameter of the reduced diameter portion with respect to the large diameter of the opposite ends of the member is limited to a certain value, while the taper angle of the conical surfaces connecting the reduced diameter portion to the opposite ends of the member is necessarily held to be the same as the wedge angle of the beveled side surfaces of the dies secured to the rolls of the apparatus, thereby giving severe restriction to the capability of the rolling forming operation.
This invention aims at avoiding the above described disadvantages of the prior art cross-rolling forming process.